Necessary preferences
The calculators store unit preference (km or miles), last 5K, 10K, half-marathon, and marathon target times, and your cookie-banner choice in localStorage on this device. Other calculator fields are not saved. These preferences are necessary for the site to remember units and race targets. They are not used to identify you across other websites.
Optional analytics
If you accept, we load Google Analytics 4 to measure page views and which calculators people open. Events do not include your race times, heart rate, age, or other inputs. Google may set cookies such as _ga and _ga_*. These are optional. Advertising cookies are not used.
Your choices
Accept or reject optional analytics here, or from the banner on first visit. Reject still keeps necessary preferences working. If you reject after a previous accept, Google Analytics stops and its cookies for this site are deleted. You can also clear this site’s data in your browser.